Fuse



April 26, 1949. c. H. G. VAlL' FUSE Filed Aug. 29, 1945 FIGZQ ATTORNEY Patented Apr. 26, 1949 UNITED STATES PATENT OFFICE FUSE Chester H. G. Vail, New York, N. Y. Application August 29, 1945, Serial No. 613,271

1 Claim.

The invention relates to fuses and particularly to the plug type of fuse used in ordinary electric circuits in which the fuses function to blow when the circuit is overloaded.

The plug fuse in most common use at the present time is of a screw type and is non-reusable or in other words after the fusible element has been destroyed by an overloading of the circuit the entire plug is removed and discarded and a new one threaded into the socket. Ofttimes the fuses are located in a somewhat dark and more or less inaccessible position and difliculty is encountered in unscrewing the used fuse and screwing in a new one and there is always the possibility, particularly with an inexperienced person, of receiving disagreeable and uncomfortable electric shocks. One of the objects of the present invention is to remedy this condition. In accordance with the invention, a novel fuse plug is provided, the body portion or adapter of which is inserted into the fuse plug socket and remains there indefinitely. The fuse bearing device which carries the fusible material is of a pull type and is so designed that it may be removed and a new one inserted with the greatest of ease, even by a child, and all possibility of receiving electrical shocks are precluded.

Naturally, the well known type of throw away plugs are not unduly expensive but material savings are effected with a fuse plug built in accordance with the present invention. The body portion or adapter is permanent and the only part thrown away is the pull member carrying the fusible material and this member is comparatively inexpensive.

A further important object of the invention is to provide a visible means whereby one may readily ascertain which particular fuse is burnt out on a panel or fuse box where a plurality of fuses are located.

Other objects are to provide a fuse plug which is neat in appearance, is of a rugged and durable construction and one that will be of maximum efficiency in practice.

Still other objects and advantages will become apparent as this specification proceeds. Referring to the drawings forming a part thereof and in which one embodiment of the invention is illustrated:

Fig. 1 is an elevational view of the assembled plug;

Fig. 2 is an elevational view taken at right angles to Fig. 1;

Fig. 3 is a longitudinal sectional view of the adapter; parts being in elevation;

Fig. 4 is an elevational view, parts being in section, of the fuse bearing device;

Fig. 5 is a longitudinal sectional view taken on the line 5-5 of Fig. 4; and

Fig. 6 is a sectional plan View taken on line 66 of Fig. 5.

Referring again to the drawings, the reference numeral [0 designates the adapter and H the fuse bearing device. In Figs. 1 and 2 the two parts are illustrated in their assembled relation to each other.

The adapter I 0 comprises a body portion [2 made of Bakelite or some other analogous fire resisting insulating material. Two receiving sockets i3, I 4 are provided and these sockets communicate with a recess l5 extending across or part way across the upper end of the body portion. A metallic shell is provided with conventional rolled threads encloses the lower part of the body portion.

A washer 20 made of insulating or non-conductive material overlays the fiat part or bottom of the shell t6 and a headed pin or stud 2! passes through suitable apertures in the washer and shell and is entered into the body portion to hold the parts in assembled relation. The stud may be knurled or roughened as indicated in Fig. 3 to insure better functional engagement.

The exposed end 22 of the stud acts as the conventional contact and a contact strip 23 is secured under the head and passes through suitable openings in the Washer and shell and enters the receiving socket l3. The contact strip may be slightly bowed as indicated at 24 in Fig. 3 to provide a better contact as will be apparent hereinafter.

Another contact strip 25 is positioned in the receiving socket I4 and the lower end of this strip is turned and engages the shell I 6 so that the shell I 6 is in the electrical circuit in a conventional manner. The contact strip 25 may also be bowed as indicated at 26 in Fig. 3 for the same purpose as that explained in connection with the strip 23. The arrangement of the shell [6, its contacts and associated parts might be widely varied.

The fuse bearing device ll, particularly illustrated in Figs. 4, 5 and 6 comprises a body portion 30 of insulation having a finger gripping means 3| appended thereto and a pair of prongs 32 depending therefrom. In the assembled position the prongs 32 enter the receiving sockets I3 and I4 and the body portion 30.0ccupies the transverse recess i5 with the finger gripping means 3| extending above the adapter as shown in Figs. 1 and 2. The finger gripping means 3| 'tangular in formation.

is apertured as indicated at 33 to facilitate removal or entering of the fuse bearing device. The fuse bearing device is entirely or in part made of Pyrex or some other clear plastic in order that the fusible element hereinafter described be visible.

The fusing element comprises a strip formed of any suitable known material having a comparatively low melting point. This strip is bent in U-shape as particularly shown in Fig. 4 and may be mounted in the pull fuse in various manners.

As illustrated in Figs. 4 to 6 the exposed ends 35 of the strip of fusible material overlay both the inner and the outer sides and ends of the prongs 32. They are bent at right angles and extend over the ends of the prongs and thence upwardly into the body portion where they are connected at 36. The connecting portion 35 is weakened and naturally this will be the portion which will blow when an overload occurs.

As illustrated in Figs. 4, 5 and 6, the body portion of the fuse device 30 is provided with a pocket 40 between the prongs 35 which might be-rec- The connecting portion 36 of the fusible strip 35 is entered into this pocket and a small thin rectangular sheet M of resilient material such as fiber is pressed into the mouth of the pocket to retain the fusiblestrip in proper relation to the fuse bearing device. The forward and rearward portions of the pocket are provided with shallow grooves or indentations as indicated at B in Figs. and 6, thus insuring against any possibility of sheet 41 becoming displaced.

When the fuse bearing device is inserted in the adapter the exposed ends 35 of the fusible material engage the contact strips 23 and to com-- plete the electrical circuit. The transverse recess 15 with the receiving soclzets l3 and I4 communicating therewith is an important element of the invention. By virtue of this construction one may easily insert the fuse bearing device. in the dark and entirely by the sense of touch. The two prongs 32 are entered into the recess l5.and.all one has to do is to move them backand forth a .little until the prongs find thev receiving sockets and then they are pushed home.

The general practice fuses are housed in a wall box or situated on a panel andas a rulea'num- .ber of circuits conjoin in such a location which necessitates a plurality of fuses being provided.

When a fuse blows on one circuit, particularly where the wall box or panel is in a dark place as they generally are, due to being more or less unsightly, considerable difficulty is encountered before finding out which fuse has blown. One of the important aspects of the present invention is to provide a means whereby it may be readily and immediately ascertained which fuse has burnt out.

Changes in details of construction and arrangement of parts such as would occur to one skilled in the art are to be considered as coming within the spirit of the invention as expressed in the appended claim.

I claim:

A fuse comprising a body, having a handle and a pair of depending prongs, a fusible strip carried by the said body, said strip being substantially U-shaped, extending from the body along the outside of said prongs, covering both prongs on the opposite faces and the ends thereof, said body having a pocket between said prongs at the junction thereof with said body, and a retaining sheet in said pocket overlying part of said strip,

, the body engaging the edges of said sheet to hold the same in place.

CHESTER H. G. VAIL.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 970,088 Murray Sept. 13, 1910 1,435,651 Murray, 12, et a1. Nov. 14, 1922 1,488,420 Watts 1- Mar. 25, 1924: 1,509,702 Berrian Sept. 23, 1924 1,545,781 Long July 14, 1925 1,569,972 Glowacki Jan. 19, 1926 1,634,810 Wheeler July 5, 1927 1,671,640 I-Iendry May 29, 1928 1,726,389 Engelhardt Aug.-27, 1929 1,772,261 McCarthy Aug. 5, 1930 1,798,174 Sheller Mar. 31, 1931 1,921,096 Peterson Aug. 8, 1933 1,926,4 1 Klopfenstein Sept. 12, 1933 2,003,792 Rosenbauni June 4, 1935 2,030,115 Muldoon Feb. 11, 1936 2,074,400 Kauffman s Mar. 23, 1937 2,206,787 Linton July 2, 1940 

